STTR Phase I: Fabrication of Blue/UV Lasers and Laser Systems

This Small Business Technology Transfer (STTR) Phase I research project proposes to develop new methods for blue/UV laser fabrication. These new devices will have the competitive advantages of higher emission intensities, higher reliability, and ability to extend emission into the deep UV spectral range. Fabricated devices will consist of cleaved AlGaN epitaxial layer structures on the tips of copper bars. Such semiconductor material packaging will significantly improve heat dissipation from large band gap AlGaN semiconductor active region materials. Enhanced active region heat dissipation will allow operation with much higher injection currents and correspondingly higher light output. Research will focus on adapting a metallization, bonding, and cleaving technique originally developed at the University of Oklahoma for mid-IR laser fabrication using IVVI semiconductor epitaxial layer materials. The project will also focus on developing a low cost electronics system capable of measuring short fluorescence lifetimes. Work on the electronics portion of this project will be devoted to the design of a small circuit board populated with a low cost digital signal processor and related components. Firmware will also be written to perform a coherent under-sampling measurement algorithm that will enable accurate measurement of photodetector decay transients of 1 nanosecond or less. Advances in fabricating improved blue/UV light emitters and low cost electronics for fast photodetector signal measurements will enable development of improved chemical and biological (CB) sensors. An important outcome will be compact and low power consumption deep UV light sources; devices that will enhance the capabilities of CB sensors based on fluorescence and Raman scattering detection principles. A handheld CB sensor for distinguishing between a harmless inorganic material and a potentially harmful pathogenic biological material is just one example of a product that can be developed as a result of this project. In addition, improved blue and UV emitters can also be used for optical data storage and solid state lighting.